if the number of people who voted for the Republican in 2016 is essentially the same as the numbers doing so in 2008 and 2012 it would seem that the Republican base didn't grow, but isn't it conceivable that the base remained the same in overall number but by a combination of a loss of traditional Republicans and a gain in first time voters ("the demographic that in the past ignored many elections" rather than young people) and defecting Democrats?
That makes sense to me. It's also what Trump's vote totals by state suggest.
Nationwide, it's true, Trump didn't win more voters than Romney. Right now, he's at 60.9 million (because they're still counting votes). That happens to be exactly what Romney got too. Trump's about 30 thousand ahead.
But that overall result cloaks significant regional differences.
There were states where Trump got many fewer votes than Romney. #NeverTrumpers, maybe. Who stayed home, skipped the top line of the ballot, or switched to Hillary (or Johnson, or McMullin).
But there were also states where Trump got significantly more votes than Romney. And not because they're states particularly known for their healthy population growth.
Those must have either been Obama > Trump voters, or people who hadn't been voting previously/for a while but were activated by Trump's dog whistles.
Vote totals were hard to assess on election night because so many votes (esp mail-in ballots and the like, especially in the West) aren't counted on the night itself. But there's a running tally of the counted vote by state in this spreadsheet
I created my own spreadsheet to put those numbers next to the raw numbers by state in 2012 (don't ask why. We're all mad in our own ways).
These are the biggest outliers in terms of how many votes Trump gained/lost compared to Romney:
1. +452,463 Florida
2. +232,507 Pennsylvania
3. +163,946 Michigan
4. +149,563 New York
5. +135,579 Indiana
46. -66,084 Maryland
47. -105,793 Massachusetts
48. -201,041 Washington
49. -321,569 Utah
50. -1,487,403 California
California's number is overly low because they still haven't finished counting there. As of yesterday, for example, they still needed to count
one-third of the votes in Marin county. In this year's Democratic primary it took them a month
to finish counting. I don't know if there are other states where they still have so much to count as well. Washington and Oregon are all vote-by-mail, so maybe.
Lot of big states there obviously because they have the most voters. You could also calculate it as a relative measure, i.e. Trump's number of votes is what percentage of Romney's number of votes?
1. 116.4% West Virginia
2. 114.8% North Dakota
3. 114.6% Maine
4. 114.1% Rhode Island
5. 111.9% Delaware
46. 91.1% Massachusetts
47. 84.4% Washington
48. 79.2% Alaska
49. 69.3% California
50. 56.6% Utah
Some unsurprising names here. Trump doing particularly well in West-Virginia won't surprise many, considering how well he's done generally with white working class voters and how quickly WV has been turning dark red. Trump doing particularly well in North Dakota may have a lot to do with the many new inhabitants there who came for the oil boom. Trump's overperformance in some of northeastern states may seem surprising, but was actually foreseen by those oh-so-maligned polls
Trump doing very badly in Utah, in relative terms, won't surprise anyone (Mormons). Liberal/coastal states Massachusetts, California and Washington are also unsurprising, and Alaska more surprising, but keep in mind again that some states might not have finished counting.